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    <title>Document</title>
</head>
<body>
    <script>
        var a = 'window'
    var obj={
        a:'obj',
        b:()=>{
            let a=9
            console.log(1,this,this.a,a)
        },
        c:function(){
            var a='c'
            console.log(2,this,this.a)
            return {
                fn:()=>{
                    console.log(22,a)
                }
                
            }
        }
    }
    obj.b() // 1,
    console.log(obj.c());//function
    console.log(obj.c().fn());//undifine
    obj.b1=()=>{console.log(3,this)}
    obj.b1();
    
    </script>
    
</body>
</html>